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A fully loaded boeing aircraft has a mass of 5.4 × 10⁵ kg. Its total wing area is 500 m². It is in level flight with a speed of 1080 km/h. If the density of air is 1.2 kg m⁻³, the fractional increase in the speed of the air on the upper surface of the wing relative to the lower surface in percentage will be. (g = 10 m/s²)
- 16
- 6
- 10
- 8
Correct answer: 10
Solution
The correct option is 10% because the lift generated by the wings is proportional to the difference in airspeed above and below the wings, which can be calculated using Bernoulli's principle. The calculations show that the increase in speed on the upper surface compared to the lower surface results in a fractional increase of approximately 0.1, translating to a 10% increase.
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